A question to the Cisco boffins
This is a pig to try and explain and also research, so I'm hoping some CCNA level and above chaps on here may lend a hand here. It's not exactly serious as I have a workaround but it's something that interested me...
We have a distant site and they use bearer x to get back to the the office. Sometimes they want to switch and use bearer y. The link to bearer x and y is set on their f0/0 and f0/1 interfaces respectively.
They get back to us over a GRE tunnel. So their config looks something like this:
The distant end uses bearer x most of the time, and my plan was that if they want to use bearer y, they just unplug bearer x and then plug bearer y in to the other interface (they are labelled, so they can't mess it up).
The problem I'm having is that the router doesn't appear to be load balancing correctly. The router seems to now and again send packets to 10.10.10.2 even though that AD is set lower, this causes the OSPF LS to go to down, so the link drops. I'm seeing around 20% packet loss (while the link to the bearer remains at 100% success).
I hope I've explained this well enough? I have a feeling it's to do with the way that we use OSPF over GRE Tunnels but I'm not too sure.
This is a pig to try and explain and also research, so I'm hoping some CCNA level and above chaps on here may lend a hand here. It's not exactly serious as I have a workaround but it's something that interested me...
We have a distant site and they use bearer x to get back to the the office. Sometimes they want to switch and use bearer y. The link to bearer x and y is set on their f0/0 and f0/1 interfaces respectively.
They get back to us over a GRE tunnel. So their config looks something like this:
Code:
int f0/0
ip add 10.10.1.2 255.255.255.252
int f0/1
ip add 10.10.10.2 255.255.255.252
int tun 0
desc link to office via bearer x
ip add 192.168.0.2 255.255.255.252
tunnel source 10.10.1.2
tunnel dest 20.20.20.10
int tun 1
desc link to office via bearer y
ip add 192.168.1.2 255.255.255.252
tunnel source 10.10.10.2
tunnel dest 20.20.20.10
router ospf 10
network 192.168.0.0 0.0.0.3 area 0
network 192.168.1.0 0.0.0.3 area 0
ip route 20.20.20.10 255.255.255.0 10.10.1.1
ip route 20.20.20.10 255.255.255.0 10.10.10.1 2The distant end uses bearer x most of the time, and my plan was that if they want to use bearer y, they just unplug bearer x and then plug bearer y in to the other interface (they are labelled, so they can't mess it up).
The problem I'm having is that the router doesn't appear to be load balancing correctly. The router seems to now and again send packets to 10.10.10.2 even though that AD is set lower, this causes the OSPF LS to go to down, so the link drops. I'm seeing around 20% packet loss (while the link to the bearer remains at 100% success).
I hope I've explained this well enough? I have a feeling it's to do with the way that we use OSPF over GRE Tunnels but I'm not too sure.
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